Connector

Abstract: When a retainer is displaced into a provisionally-retained position, a slanting abutment surface of a retaining step is abutted against a rear edge of a main portion of a metal terminal disposed in a half-inserted position. Then, when the retainer is pushed, each projection is guided by a slanting portion of a guide groove, so that the retainer is displaced obliquely forwardly downwardly, and reaches a completely-retained position. During this displacement, a forwardly-acting pressing force is exerted on the metal terminal, so that the metal terminal is automatically pushed deeper into a proper inserted position.

Description: This invention relates to a connector having the function of double retaining of metal terminals by a retainer, and more particularly to a connector having the function of urging half-inserted metal terminals into a proper inserted position in accordance with the insertion of the retainer. There are known connectors having a double retaining function to be performed by a retainer. In such a connector as shown in Fig. 7, when a metal terminal c is inserted into a terminal receiving hole b in a housing a from a rear end thereof, an elastic retaining pawl d formed on an upper wall of the terminal receiving hole b is elastically deformed by this inserted metal terminal. Then, when the metal terminal reaches a proper inserted position at the inner end of the terminal receiving hole, the retaining pawl d is received in a retaining recess e , formed in the upper surface of the metal terminal c , due to its own resilient restoring force, thereby effecting a first-stage retaining in a withdrawing direction. Then, when a retainer f , inserted into a provisionally-retained position from a lower side of the housing a in a manner to generally divide the housing, is pushed in a direction of an arrow to be retained in a completely-retained position, a retaining step formed on the retainer f is received in a recess h formed in a lower surface of the metal terminal c , thereby effecting a second-stage retaining. In such a connector, the metal terminal c is inserted while elastically deforming the retaining pawl d , as described above, and therefore a considerable load is perceived halfway, and despite the fact that the metal terminal has not yet reached the proper inserted position, the inserting operation is often stopped under a mistake of facts in a half-insertedposition as indicated in a broken line in Fig. 7. If such a situation is encountered, even when the retainer f is pushed, the retaining step g is abutted against the lower surface of the metal terminal c , so that the retainer can not be inserted. In this case, the operator becomes aware of the half-inserted condition of the metal terminal c , and it is necessary for the operator to once retract the retainer f , to re-insert the metal terminal c into the proper inserted position, and then to again push the retainer f . However, since many metal terminals c have been inserted, it is not easy to find the half-inserted terminal among these terminals. And besides, such half-inserted metal terminal is not always one, and in an extreme case, all of the metal terminals must be reinserted, thus inviting a disadvantage that an extremely troublesome operation must be done. It is known from experiences that the metal terminal c is held in the half-inserted condition mainly because the retaining step g of the retainer f interferes with an end edge of a main portion i . GB-A-2 218 272 discloses with respect to Figs. 1 to 8 thereof a connector having a connector housing 1 having terminal receiving holes 2, a retainer 14 insertable into an insertion groove of the housing, whereby said retainer has communication holes 15 communicatable with the terminal receiving holes. Guide grooves 4 are formed on the connector housing and projections 16 are formed on the retainer, said projections moving along the guide grooves when the retainer is inserted. The retainer is moved from the contact-insertion position to the contact-latching position. The present invention has been made in view of the above problem, and an object of the invention is to correct a half-inserted condition of a metal terminal, thereby enabling mating connectors to be easily fitted together. The above object of the present invention is achieved by a connector according to the features of claim 1. Accordingly, the present invention provides a connector comprising a connector housing having terminal receiving holes each for receiving a metal terminal inserted from a rear end the connector housing, and a retainer insertion groove which opens to one side of said connector housing; and a retainer insertable into said retainer insertion groove, said retainer having communication holes communicatable with said terminal receiving holes, respectively, and said retainer being adapted to be retained in a provisionally-retained position where each of said communication holes does not hinder the insertion and withdrawal of said metal terminal and in a completely-retained position where said retainer is engaged with said metal terminals in a manner -to limit the withdrawal of said metal terminals, wherein guide grooves for guiding the insertion of said retainer are formed on one of said connector housing and said retainer, whereas projections for being disposed to move respectively along said guide grooves are formed on the other; said retainer can be abutted against part of said metal terminal in said provisionally-retained position when said metal terminal is disposed in a half-inserted position; and each of said guide grooves is so formed that during the time when said retainer is moved from said provisionally-retained position to said completely-retained position, said retainer can push said metal terminals from the half-inserted position into a proper inserted position. This connector is furthermore characterized in that said retainer insertion groove is formed in said connector housing to divide each of said terminal receiving holes and each of said guide groves for guiding said projection has an upper straight portion and a lower straight portion which are parallel to and offset relative to each other in front-to-rear direction, wherein a slanting portion communicates said upper and lower straight portions. When the retainer is inserted into the retainer insertion groove in the housing, the retainer reaches the provisionally-retained position, with the projections guided by and moved along the guide grooves, respectively. The metal terminals are inserted, and then when the retainer is further inserted, the retainer is displaced to the completely-retained position. If the metal terminal is disposed in a half-inserted position during the displacement of the retainer from the provisionally-retained position, the retainer is abutted against part of the metal terminal, and pushes the metal terminal into a proper inserted position during the displacement of the retainer into the completely-retained position, and also the retainer retains the metal terminals against withdrawal in this position. Even if the metal terminal is inadvertently disposed in a half-inserted position, the metal terminal can be automatically pushed into the proper inserted position in accordance with the displacement of the retainer from the provisionally-retained position into the completely-retained position. Thus, there is no need to re-insert the metal terminal, and therefore the efficiency of the operation can be enhanced greatly. The following is a more detailed description of preferred embodiments of the present invention, which is to be senn in conjunction with the accompanying drawings, in which: Fig. 1 is a partly-broken, exploded perspective view of one preferred embodiment of the present invention; Fig. 2 is a front-elevational view showing a housing and a retainer before they are assembled together; Fig. 3 is an explanatory view showing a condition in which the retainer is inserted to a position immediately before a provisionally-retained position; Fig. 4A is an explanatory view showing the retainer in the provisionally-retained position; Fig. 4B is an explanatory view showing the retainer in a completely-retained position; Fig. 5 is a view explanatory of the formation of a guide groove by molding; Fig. 6A is an explanatory view of another embodiment of the present invention in which the invention is applied to a female connector, showing a retainer in a provisionally-retained position; Fig. 6B is an explanatory view of the female connector, showing the retainer in a completely-retained position; and Fig. 7 is a cross-sectional view of a portion of a conventional construction. One preferred embodiment of the present invention, in which the invention is applied to a male connector, will now be described with reference to Figs. 1 to 5. In these Figures, a housing 1 includes a body 2 of a rectangular parallelepipedic shape, and twelve (12) terminal receiving holes 3 for respectively receiving male metal terminals 11 are formed through this body, and extend from a front side to a rear side of the housing, the terminal receiving holes 3 being arranged in three columns and four rows. A retainer insertion groove 6 for receiving a retainer 5 for retaining the metal terminals 11 in a double manner is formed in a generally central portion of an upper surface of the body 2 in a manner to divide each terminal receiving hole 3, and guide walls 7 are provided respectively on opposite (right and left) sides of this retainer insertion groove. Communication holes 9 equal in number to the terminal receiving holes 3 are formed through the retainer 5, and are communicatable with the terminal receiving holes 3, respectively. Formed respectively in opposite (right and left) sides of the retainer are downwardly-open fitting grooves 10 in which the guide walls 7 are adapted to be fitted, respectively. The retainer 5 is inserted into a predetermined position in the retainer insertion groove 6, with the two fitting grooves 10 fitted respectively on the guide walls 7, as shown in Fig. 3, and then the metal terminals 11 are respectively inserted into the terminal receiving holes 3, and are pushed to inner ends thereof, so that an elastic retaining pawl 12 (see Fig. 3) formed within each receiving hole 3 is received in a retaining recess 14 formed in an upper surface of a main portion 13 of the metal terminal 11, thereby effecting a first-stage retaining in a withdrawing direction. When the retainer 5 is further pushed, a retaining step 16, formed on an upper wall of each communication hole 9, is received in a recess 17 formed adjacent to a rear end of the main portion 13, thereby effecting a second-stage retaining, as described above for the conventional construction. Next, the structure of the insertion portion of the retainer 5 of the present invention will now be described in detail. In this embodiment, the thickness of the retainer 5 is smaller by a predetermined dimension than the width of the retainer insertion groove 6. A generally vertically-extending guide groove 19 for guiding the insertion of the retainer is formed in an outer surface of each of the guide walls 7 formed respectively on the opposite (right and left) sides of the retainer insertion groove 6. As shown in Fig. 2, the guide groove 19 has an upper straight portion 20 and a lower straight portion 21 which are parallel to each other, and are offset relative to each other in a front-to-rear direction in such a manner that inner edges of the two straight portions are disposed in a common straight line. This configuration is achieved by a mold of a special design for forming the two straight portions 20 and 21, and this will be described later in detail. The lower end of the upper straight portion 20 is connected to the upper end of the lower straight portion 21 by a slanting portion 22 slanting toward the front side. An auxiliary groove 23 of a greater depth is formed in the straight portion 20, and is disposed centrally of the width thereof, and extends from the upper end thereof to the slanting portion 22. An auxiliary groove 24 of a greater depth is formed in the straight portion 21, and is disposed centrally of the width thereof, and extends from the lower end thereof to the slanting portion 22. Each of the grooves 23 and 24 has a semi-circular cross-section, and has the end formed into a semi-spherical shape. The lower end of the auxiliary groove 23 and the upper end of the auxiliary groove 24 are separated from each other, unlike the guide groove 19. On the other hand, a projection 26 of a parallelogrammic shape is formed on that surface of each of the right and left fitting grooves 10 of the retainer 5 facing that surface of the guide wall 7 having the guide groove 19 formed therein, and the projection 26 is formed at a predetermined position, and can be intimately fitted in and slide along the straight portions 20 and 21 and the slanting portion 22 of the guide groove 19. Further, a projection 27 of a semi-spherical shape for fitting in the auxiliary groove 23, 24 is formed on the surface of the projection 26. With respect to the guide groove 19, the lower straight portion 21 is not always necessary in view of the function of this embodiment described later in detail, and also the auxiliary groove 24 may be replaced by a semi-spherical hole for receiving the projection 27 which hole is formed at the position where the upper end of the lower auxiliary groove 24 is disposed. Furthermore, it is not necessary that the inner edges of the two straight portions 20 and 21 should be disposed in a common straight line, and this configuration is adopted for the convenience of the formation of the guide groove 19 by molding. More specifically, for forming the guide groove 19 by molding, a pair of upper and lower slide cores x and y each having an inclined front end are used, as shown in Fig. 5, and the cores x and y serve to form the upper and lower straight portions 20 and 21, respectively, and also serve to form halves of the slanting portion 22, respectively. Merely by withdrawing the upper and lower cores x and y in directions of arrows, respectively, the upper and lower straight portions 20 and 21 and the slanting portion 22 are simultaneously formed by molding. Namely, the removal of a mold portion in a direction away from the front surface of the sheet of Fig. 5 is omitted, thereby reducing the manufacturing cost. The front edge of the retaining step 16, formed on the upper wall of each communication hole 9 in the retainer 5, is cut to form a slanting abutment surface 29 which allows a smooth pushing of the metal terminal 11. The operation of this embodiment will now be described mainly with reference to Figs. 3 and 4. First, the retainer 5 is brought into registry with a rear portion of the retainer insertion groove 6, and is inserted thereinto. At this time, each projection 26 and each projection 27 of the retainer 5 are fitted respectively in the upper straight portion 20 of the guide groove 9 and the auxiliary groove 23 during the insertion, and the retainer is inserted straight downward while guided by these portions. When each projection 26 and each projection 27 reach the lower ends of the upper straight portion 20 and the auxiliary groove 23, respectively, a resistance is perceived, and the insertion operation is stopped once, so that the retainer 5 is stopped at a position slightly before a provisionally-retained position. In this condition, the metal terminals 11 are inserted into the terminal receiving holes 3 of the housing 1, respectively, as described above. Then, when the retainer 5 is further pushed, the projection 27 is disengaged from the lower end of the auxiliary groove 23, and is brought into contact with the bottom surface of the slanting portion 22 of the guide groove 19 as shown in Fig. 4A, and the projection 26 is guided along this slanting portion 22, so that the retainer 5 is slightly displaced obliquely forwardly downwardly to reach the provisionally-retained position. In this provisionally-retained position, the projection 27 is held in contact with the bottom surface of the guide groove 19, as described above, and therefore because of a frictional engagement between the two, for example, when transporting a provisionally-assembled structure comprising the housing 1, the retainer 5 and the metal terminals 11, the retainer 5 will not be easily disengaged, and also the retainer 5 will be effectively prevented from being accidentally displaced into a completely-retained position. If any of the metal terminals 11 has not yet reached the proper inserted position, and hence is disposed in a half-inserted position when the retainer 5 is displaced into the above provisionally-retained position, the slanting abutment surface 29 on the front edge of the retaining step 16 of the retainer 5 is abutted against a rear edge of the main portion 13 of the metal terminal 11 disposed adjacent to the recess 17, as shown in Fig. 4A. In this condition, when the retainer 5 is further pushed, the projection 26 is guided by the remaining portion of the slanting portion 22, and the retainer 5 is further displaced obliquely forwardly downwardly, so that the retainer 5 is abutted at its lower surface against the bottom surface of the retainer insertion groove 6, and hence reaches the completely-retained position, thus stopping the displacement, as shown in Fig. 4B. At this time, the projection 27 is fitted in the upper end of the lower auxiliary groove 24, thereby retaining the retainer 5 against upward movement. During the time when the retainer 5 is displaced obliquely forwardly downwardly from the provisionally-retained position to the completely-retained position, the metal terminal 11 receives a forwardly-acting pressing force to be pushed into the proper inserted position, so that the first-stage retaining by the elastic retaining pawl 12 is effected, and also the retaining step 16 of the retainer 15 is fitted in the recess 17, thereby effecting the second-stage retaining. Thus, in this embodiment, even if the metal terminal 11 is inadvertently held in a half-inserted position, the metal terminal can be automatically-pushed into the proper inserted position in accordance with the displacement of the retainer 5 from the provisionally-retained position to the completely-retained position, and therefore there is no need to re-insert the metal terminal 11. In the structure of this embodiment, by bringing each projection 27 of the retainer 5 into contact with the bottom surface of the slanting portion 22 of the guide groove 19, the retainer 5 can be easily locked in the provisionally-retained position in such a manner that the retainer can not be displaced upwardly and downwardly. Also, by fitting the projection 27 in the upper end of the lower auxiliary groove 24, the retainer can be held in the completely-locked position against upward movement. In order to confirm the direction of the retainer 5, forwardly downwardly-slanting surfaces 32 and 33, which are parallel to the slanting portion 22 of the guide groove 19, and can be mated with each other, may be formed on a lower surface of a projected portion 31 formed on the upper rear edge of the retainer 5 and the upper rear edge of the retainer insertion groove 6, respectively, in which case in addition to the fitting of the projection 26 in the slanting portion 22 of the guide groove 19, a relative sliding movement between the slanting surfaces 32 and 33 serves to guide the oblique displacement of the retainer 5. In the above embodiment, although the invention is applied to the male connector, the invention can be applied to a female connector, as shown in Fig. 6. In this case, similarly, a guide groove 19 and auxiliary grooves 23 and 24 are formed in each of two guide walls 7 provided respectively at opposite sides of a retainer insertion groove 6 in a housing la, and a projection 26 and a projection 27 are formed on that surface of each fitting groove 10 of the retainer 5 facing the guide wall. With this arrangement, during the time when the retainer 5 is displaced from a provisionally-retained position (Fig. 6A) to a completely-retained position (Fig. 6B), those metal terminals lla disposed in a half-inserted position can be pushed into a proper inserted position, as described above. Of course, in either of the above connectors, the guide groove 19 and the auxiliary grooves 23 and 24 may be provided at each fitting groove 10 of the retainer whereas the projection 26 and the projection 27 may be formed on that surface of the guide wall 7 of the retainer insertion groove 6 facing these grooves.

Claims: A connector comprising: a connector housing (1) having terminal receiving holes (3) each for receiving a metal terminal (11) inserted from a rear end into the connector housing (1), and a retainer insertion groove (6) which opens to one side of said connector housing (1); and a retainer (5) insertable into said retainer insertion groove (6), said retainer (5) having communication holes (9) communicatable with said terminal receiving holes (3), respectively, and said retainer (5) being adapted to be retained in a provisionally-retained position where each of said communication holes (9) does not hinder the insertion and withdrawal of said metal terminal (11) and in a completely-retained position where said retainer (5) is engaged with said metal terminals (11) in a manner to limit the withdrawal of said metal terminals (11), wherein guide grooves (19) for guiding the insertion of said retainer (5) are formed on one of said connector housing (1) and said retainer (5), whereas projections (26) for being disposed to move respectively along said guide grooves (19) are formed on the other; said retainer (5) can be abutted against part of said metal terminal (11) in said provisionally-retained position when said metal terminal (11) is disposed in a half-inserted position; and each of said guide grooves (19) is so formed that during the time when said retainer (5) is moved from said provisionally-retained position to said completely-retained position, said retainer (5) can push said metal terminals (11) from the half-inserted position into a proper inserted position, characterized in that said retainer insertion groove (6) is formed in said connector housing (1) to divide each of said terminal receiving holes (3) and each of said guide groves (19) for guiding said projection (26) has an upper straight portion (20) and a lower straight portion (21) which are parallel to and offset relative to each other in front-to-rear direction, wherein a slanting portion (22) communicates said upper and lower straight portions (20, 21). The connector as claimed in claim 1, wherein said upper straight portion (20) and said lower straight portion (21) are offset relative to each other in front-to-rear direction in a manner that inner edges of the two straight portions (20, 21) are aligned in a common straight line. The connector as claimed in claim 1 or 2, wherein said connector housing (1) further comprises a pair of guide walls (7) at opposite sides of said retainer insertion groove (6). The connector as claimed in claim 3, wherein said retainer (5) has two leg portions to form fitting grooves (10) downwardly opened to be fitted with said guide walls (7). The connector as claimed in claim 3 or 4, wherein said guide grooves (19) are formed on said guide walls (7), and said projections (26) are formed on said leg portions. The connector as claimed in anyone of claims 1 to 5, wherein a width of said retainer (5) is less than a width of said retainer insertion groove (6) by a predetermined width. The connector as claimed in claim 1, wherein each of said projections (26) have a parallelogrammic shape with a pair of sides which contact the edges of said straight portion (20, 21) of the guide groove (19), and the other pair of sides contact with edges of said slanting portion (22). The connector as claimed in anyone of claims 1 to 7, wherein said guide groove (19) has an auxiliary groove (23, 24) of greater depth running centrally with respect to the width of the guide groove (19). The connector as claimed in claim 8, wherein a further projection (27) having a semi-spherical projection is provided at said retainer (5) to be fit with said auxiliary groove (23, 24).

Inventors: NABESHIMA AKIRA, SABA TOSHIKAZU, WATANABE KAORU, NABESHIMA, AKIRA, SABA, TOSHIKAZU, WATANABE, KAORU, NABESHIMA, AKIRA, C/O SUMITOMO WIRING SYST., LTD., SABA, TOSHIKAZU, C/O SUMITOMO WIRING SYST., LTD., WATANABE, KAORU, C/O SUMITOMO WIRING SYST., LTD.
Applicants: SUMITOMO WIRING SYSTEMS, SUMITOMO WIRING SYSTEMS, LTD.
Application year: 1994
Main classification: H01R13
IPC codes: H01R13, H01R43